Condensate Pot Water Hammer Due to Failed Steam Traps

This is the most common cause of condensate pot water hammer. To confirm, perform acoustic or temperature testing on the steam traps immediately upstream of the condensate pot. A trap that is 'failed open' will show a temperature profile identical to the supply line, indicating live steam is blowing through into the condensate network. A trap that is 'failed closed' will exhibit a significant temperature drop and lack of discharge flow, causing condensate to back up into the steam line. The presence of these failed traps directly leads to the mixing of steam and cold liquid that creates hydraulic shock.

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